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Susceptibilities and Spin Gaps of Weakly-coupled Spin Ladders

S. Larochelle·M. Greven
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Abstract

We calculate the uniform and staggered susceptibilities of two-chain spin-1/2 Heisenberg ladders using Monte-Carlo simulations. We show that the gap extracted from the uniform susceptibility and the saturation value of the staggered susceptibility are independent of the sign of the inter-chain coupling J_perp in the asymptotic limit |J_perp|/J -> 0. Furthermore, we examine the existence of logarithmic corrections to the linear scaling of the gap with |J_perp|.

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S. Larochelle, M. Greven. 2004-01-15. Susceptibilities and Spin Gaps of Weakly-coupled Spin Ladders. https://doi.org/10.1103/physrevb.69.092408

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